杂多酸型离子液体的合成及在酯化反应中的应用

摘要

用已制备的一种离子液体 IL1进行离子交换,合成了一种杂多酸型离子液体 IL2,通过核磁共振波谱,红外光谱以及热重分析技术对结构进行了表征。其中 NMR对 IL2结构上的碳氢进行了确定,IR表征了 keggin结构,TG曲线表明具有良好的热稳定性。最后,将其应用于乙酸和乙醇的酯化反应。通过对反应时间、温度、酸醇物质的量比、催化剂用量的考察,结果表明,70℃下,反应5 h,酸醇物质的量比为1∶5,催化剂和酸物质的量比为1∶300时,反应效率可达到92.31%。%Through anion exchange,heteropolyacid ionic liquids named IL2 were prepared,using a kind of ionic liquids named IL1 which was synthesised before,1 H-NMR,13 C-NMR,FT-IR and TG confirmed the structure of IL2.The results of NMR determine the structure of C and H to the IL2,IR shows that the molecular compound kept keggin structure,and TG illustrates that IL2 possessed good thermal stability.Finally,it was applied in catalytic esterification reaction of acetic acid and ethanol.By changing the reaction time,temperature,molar ratio of acid and alcohol,anount of catalyst,The results show that the optimal conditions are as follows:under 70 ℃,5 h,molar ratio of acid and alcohol is 1∶5,molar ratio of catalyst and acid is 1∶300, reaction efficiency can be up to 92.31%.